This invention relates to an adjusting device through which a predetermined clearance can be set easily and accurately between a certain member and another member. For example, such a clearance adjusting device may be applied to a control cable of normally non-contacting type clutch system for an automotive vehicle.
FIG. 1 shows a conventional normally noncontacting type clutch system. A cable guide 13 with a long through hole 13b is fixed on a portion of a vehicle body 16 by a bolt 30. One end of an outer cable 10 is fixed to a clutch housing 1, and the other end of the cable 10 has a male screw portion 11 to be screwed with a double nut 12. The male screw portion 11 penetrates through the cable guide 13 in its longitudinal direction. An inner cable 4 is connected at its one end to the upper end of a clutch pedal 14. The other end thereof is connected to the upper end of a withdrawal lever 2.
In the above-stated clutch system, when the clutch pedal 14 is kicked down in a well know manner, the inner cable 4 is pulled along the outer cable 10 to rotate the withdrawal lever 2 around a pivot 2a counter-clockwise in FIG. 1. Thus, a release bearing 3 presses the central portion of a diaphragm 5 to release a facing 6 from a flywheel 9. In order to arrange the facing 6 in position in relation to the flywheel 9, a predetermined clearance A between the withdrawal lever 2 and the release bearing 3 must be set. The rotation amount of the clutch pedal 14 changes due to a stretch of the inner cable 4 and the wear of the facing 6. Therefore, a clearance must be often adjusted so that each member can work accurately. For such an adjusting purpose, the double nut 12 is usually used. In such a case, a clearance A' is set between the cable guide 13 and the double nut 12 after a power portion 2b of the withdrawal lever 2 is pressed onto the release bearing 3 with no clearance therebetween, for example, by inserting a gauge of a given thickness between the double nut 12 and the cable guide 13. However, such a setting operation is cumbersome. The double nut 12 can be set by one's eye measurement, but inaccuracy often occurs. Another disadvantage is that the double nut 12 may be loosened by its vibration. An E-ring can be used for the clearance adjusting purpose, but it is formed with some grooves so that an optimum clearance can not easily be set.